Basic fibroblast growth factor and ultraviolet B transform melanocytes in human skin

Area of Science:

• Dermatology
• Oncology
• Molecular Biology

Background:

• Ultraviolet (UV) radiation is a known risk factor for melanoma.
• Melanoma development involves melanocyte proliferation, potentially influenced by growth factors.
• Basic fibroblast growth factor (bFGF) is a key autocrine growth factor in melanoma progression.

Purpose of the Study:

• To investigate the role of basic fibroblast growth factor (bFGF) in melanoma induction.
• To determine if bFGF combined with UV radiation can initiate melanoma development.
• To explore the co-carcinogenic influence of microenvironmental growth factors.

Main Methods:

• Overexpression of bFGF using adenoviral gene transfer in human skin xenografts.
• Exposure of bFGF-treated skin xenografts and skin reconstructs to UVB radiation.
• Immunofluorescence analysis to assess melanocyte proliferation, hyperpigmentation, and atypia.

Main Results:

• bFGF overexpression alone induced pigmented macules, melanocyte hyperpigmentation, proliferation, and hyperplasia, but not malignancy.
• Combined bFGF overexpression and UVB exposure resulted in pigmented lesions with hyperplastic melanocytes, including one with high-grade atypia.
• Overexpressed bFGF in dermal fibroblasts demonstrated the co-carcinogenic role of microenvironmental growth factors.

Conclusions:

• An imbalance in skin growth factor production, specifically bFGF, may contribute to melanoma development alongside UVB exposure.
• This study provides the first evidence for the co-carcinogenic effect of microenvironmental growth factors and UV radiation in melanoma initiation.
• Understanding growth factor roles is crucial for developing novel melanoma prevention and treatment strategies.